Soybeans (Glycine max L. Merr.) are a major cash crop and investment commodity in North America and elsewhere. Soybean is the world's primary source of seed oil and seed protein. Improving soybean tolerance to diverse and/or adverse growth conditions is crucial for maximizing yields. Studies have shown that even mild IDC symptoms are an indication that yield is being negatively affected (Fehr (1982) J Plant Nutr 5:611-621).
Iron-deficiency chlorosis (IDC, or FEC), reduces soybean yields. Iron is required for the synthesis of chlorophyll and, although the amount of iron is sufficient in most soils, it is often in an insoluble form that cannot be used by the plant. Iron deficiency is typically associated with soils having high pH, high salt content, cool temperatures or other environmental factors that decrease iron solubility. Chlorosis develops due to a lack of chlorophyll in the leaves of affected plants, manifesting as yellowing of the leaves.
There remains a need for soybean plants with improved tolerance to iron deficiency and methods for identifying, selecting and providing such plants, including improved markers for identifying plants possessing tolerance or susceptibility.